Silicon alloy and its use in the treatment of iron and steel



Patented Dec. 16, 1941 SILICON ALLOY AND ITS USE IN, THE

TREATMENT OF IRON AND STEEL Augustus B. Kinzel, Douglaston, N. Y., assignor to Electro Metallurgical Company, a corporation of West Virginia No Drawing. Original application January 19,

1940, Serial No. 314,575. Divided and this application September 24, 1940, Serial No. 358,104. In Great Britain April 15, 1939 1 Claim.

This invention comprises improvements in'silicon alloys and in particular silicon alloys of the class containing calcium.

Silicon-calcium alloys have long been used in metallurgical operations, for instance as deoxi- 40% calcium (part of the calcium being sometimes replaced by aluminum or manganese) and the remainder silicon except for incidental impurities such as iron. The silicon content is most usually between 50% and 65%.

An object of this invention is to provide an alloy, of the kind described above, which is.

cheaper to manufacture and which has an in creased field of utility than previously known alloys of this kind.

Another object is to provide a novel process for making alloys of the kind described above.

I have now found that a partial substitution of calcium by barium in such alloys provides certain advantages not to be expected from such substitution. A silicon-calcium-barium alloy containing 1 part of barium to 3 parts of calcium is an example within this invention. It is preferred that the ratio of barium to calcium be within the range of 1:3 to 3:1.

One advantage is the relatively great density of molten-alloys of silicon, calcium, and barium as compared with molten silicon-calcium alloys therefore impossible to prevent, by ordinary means, great losses of alloy by volatilization. 0n

the contrary, the silicon-calcium-barium alloys (with or without-moderate proportions of aluminum or manganese or both) are dense enough to permit the melter to cover them with a protective slag which minimizes losses by volatilizetion.

Other advantages are that the silicon-calciumbarium alloys are more effective, volume for volume and in some instances even pound for pound, than the silicon-calcium alloys of the same alkaline earth metal percentage, in metallurgical uses and in other uses such as in explosives.

The alloy of the invention may be made by melting its ingredients under a suitable slag, 'for instance an alkaline earth metal silicate; or by reducing under a suitable slag a mixture of silica with the oxides (and/or carbonates) of calcium and barium, the reducing agent being carbon or aluminum; or by reducing under a suitable slag a mixture of silica and barium oxide or carbonate, using calcium carbide as the reducing agent; or by reducing with silicon, under a suitable slag, a mixture of the oxides (and/orcarbonates) of calcium and barium. In all of these methods, the use of a-supernatant slag protects the bath of metal and prevents excessive losses by volatilization.

This is a division of my application Serial No. 314,575, filed January 19, 1940.

I claim:

In the art of adding to molten ironor steel an alloy containing essentially to silicon and 15% to 40% calcium, the improvement which comprises covering said iron or steel with a molten slag, and replacing a part of the calcium of said alloy with barium, so said alloy is sufliciently heavy to'remain below said slag.

AUGUSTUS B. KINZEL. 

